Protecting-housing for cutting mechanisms.



G. W. SM PROTEOTING HOUSING POR C G MECHANISMS. 4 IIIIIIIIIIIIII BDvJULY 10,1912.

1,058,339. l l Patented Apr..r 8, 1913.

GEORGE W. SMITH, OF ST. LOUIS, MISSOURI.l

rRoTEcTrNG-Housrivo ron CUTTING Mrici-IANIsMs.

- Specification of Letters Patent.

Patented Apr. 8, 1913.

Application led July 10, 191,2. Serial No. 708,667.

To all whom t may concern.'

Be it known that I, GEORGE W. SMITH, a citizen of the United States,residing at St.' Louis, Missouri, have invented a certain newand usefulImprovement in Protecting- Housing for Cutting Mechanisms, of which thefollowing is a full, clear, and exact de-v scription, such as willenable others skilled' in the art to which it appertains to make and usethe same.

This invention relates to safety devicesl such as are used on machinesprovided with cutting devices, for protecting the opera-l tor frominjury by said cutting devices.

The main object of my invention is to provide an eflicient andinexpensive safetyv device of the character referred to that can beapplied easily to various types of machines that comprise a feed t-ableand a revolving cutter-head arranged in an opening in said table.

Another object is to provide a safety device which is so constructedthat ships from the cutter-head cannot lodge on the guard members whenthey are retracted and thus prevent them from moving automatically intooperative position when they are released. 1

I have herein illustrated my invention in combination with awood-working machine for planing boards but I donot wish it to beunderstood that my invention is limitedto use in such machines for mybroad idea` consists in a housing combined with a cutting mechanism andmeans for causing said entire housing or a portion of same to moveautomatically into` an inoperative position and thus expose the cuttingymechanism when the article being operated on is presented to the cuttingmechanism.

Figure l of the drawings is a vertical sectional view illustrating myimproved safety device applied to a wood-working machine; and Fig. 2 isa topv plan view of the mechanism illustrated in Fig. 1.

Referring to the drawings which illustrate the preferred form of myinvention, A designates the table of the machine over which theAmaterial is fed by some suitable mechanism not shown', and B designatesa revolving cutter-head arranged under the table in alinement with atransversely ex-I tending opening l in the table and provided with oneor mo-re cutters 2 that engage the article being operated on when itpasses over the opening 1 in the table.

My invention consists in a safety device for protecting the operatorfrom injury by the knives or cutters in the cutter-head B, and in theembodiment of my invention herein shown, said safety device comprises ahousing or shield that normally extends over the cutter-head opening lin the table and an operating mechanism for said housing which causesthe housing to move automatically into an inoperative position when theboard or other article m being operated on is fed over t-he table A. Iprefer to form said-shield or housing from a number of substantiallyarc-shaped members 3 that are arranged in a tr-ansverse slot 4 in thetable A and which normally extend over the cutter-head opening l in thetable, as shown in full lines in Fig. 2 and in broken lines in Fig. l,thus forming a sectional housing or shield for the cutter-head.

The mechanism that I prefer to use for operating said housing so as toretract it or move it into an inoperative position consists of aplurality of spring-actuated plungers 5 arranged in openings in thetable A in advance of the cutter-head, and means cooperating with saidplungers for retracting the housing members 3 or drawing them downwardlythrough the slot 4 in the table when said plungers are depressed by theboard or article that is being fed through the machine. One plunger oractuating device 5 is provided for each section 3 of the housing, andaseparate and distinct means is employed for transmitting movement fromeach'plunger to its' cooperating housing section, thereby permitting oneor more sections of the housingl to remain in operative position when adifferent section of the housing is retracted or moved into aninoperative position so as to expo-se the cutterhead. As shown in Fig.l, each of the plungers 5 is'provided at its lower end with an angulararm athat is pivotally connected to a lever 6, which lever is providedat its front end with a rack 6a that meshes with a pinion 7. An arm 8 isrigidly connected to the pinion 7 by pins 8a, or in any other suitablemanner, and a link 9 is pivotally connected at its lower end to `the arm8 and at its upper end to the coperating housing section 3. f

A bracket 10 which is arranged on the under side of the table supports ahori- `zontally disposed countershaft 11 on which all of the levers 6are fulcrumed, and a,

, said plunger, thereby second bracket 12 is also arranged'on the underside of the table to support a shaft 13 o-n which all of the pinions 7are loosely mounted. rIhe downward pressure which the board x exerts onthe plunger 5 when said board is traveling over the table A depressessaid plunger and thus automatically retracts the housing section 3 thatcooperates `with same, and after said board has passed beyond the slot 4the housing section 3 is moved automatically back to its formeroperative position by means of a coiled expansion spring 14 that isarranged on the shank o-f the plunger 5 between the head thereof and aspring-supporting plate 15 that extends transversely under the table A,the upward movement of said plunger being limited by a stop 16 thereonthat strikes against the under side of the plate 15, as shown in Fig. 1.

The front sides or edges of the heads of the plungers 5 are preferablyinclined or beveled, as shown in Figs. 1 and 2, so that they will notinterfere with theforward movement of the article that is being fed overthe table A, and the links 9 that connect the arms 8 to their coperatinghousing sections 3 are preferably provided at their lower ends withlaterally projecting lugs or stops 9a that strike against the arms 8 andthus reduce the tendency of said links to bend when the arms 8 moveupwardly so as to restore the housing to normal position. Thetransversely extending slot 4 in the table in which the housing sections3 are arranged, is inclined, as shown in Fig. 1, so

that it will act as a guide for the members 3, and a stationary member17 which is arranged under the table underneath the cutter-head, isprovided with a vertically disposed portion 17a that acts as a guide forthe upper ends of the links 9, thereby causing the housing sections tomove in an arc into and out of operative position. A guard 18 ispreferably arranged on the under side of the table adjacent thecutter-head, as shown in Fig. l, so as to prevent the chips from flyinginto the space that the housing members 3 occupy when they areretracted.

Normally, the members 3 that form the housing or shield for thecutter-head are arranged in operative position over the cutterheadopening 1 in the table A, as shown in broken lines in Fig. 1 and in fulllines in Fig. 2. vWhen an article is fed over said table the front endof' the article strikes against the plungers 5 arranged in the line oftravel of said article and thus depresses causing the housing member ormembers 3 that coperate with said plungers to be retracted automaticallyor moved into an inoperative position so as to expose the cutter-head,the number of yhousing members that are retracted of course, dependingupon the width of the article w being operated on. As soon as saidarticle passes beyond the slot Il the housing members 3 that wereretracted are restored automatically to normal position over thecutter-head.

A safety device of the construction abovedescribed eliminates thepossibilit-y of the operator being injured by the cutter-head of themachine because it comprises a housing or shield which is alwaysarranged in operative position over the cutter-head cxcept just beforethe front end of the article reaches the cutter-head, the mechanism thatoperates the shield or housing being so designed and arranged that thehousing follows the article as it passes over the cutterhead. The factthat the housing is moved automatically both into and out of operativeposition eliminates the possibility of a careless workman forgetting torestore the housing to operative position over the cutter-head after anarticle has been fed through the machine. Another desirable feat-ure ofsuch a safety device is that only a portion of the cutter-head isexposed when a narrow article or article of less width than the entirecutter-head is fed through the machine. The device comprises only a fewparts which are of such simple construction that they are not liable toget out of order; and still another desirable feature of such a device-is that it can be applied easily to machines without materiallymodifying or re-designing the machine so as to permit the device to beattached.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a machine of the character described, a table, a cutter-headarranged in an opening in said table, a shield or housing forprotect-ing said cutter-head, a springactuated plunger arranged in saidtable in advance of said cutter-head, a lever arranged on the under sideof the table and connected by a link to said plunger, a pinion meshingwith a rack on said lever, a rigid arm on said pinion operativelyconnected to said housing by means of a link, a guideway on the underside of the table for receiving said housing when it is in aninoperative position, and a chip guard arranged between said guidewayand the cutter-head.

2. In a machine of t-he character described, a table, a cutter-headarranged in a transverse opening in said table, a plurality ofarc-shaped housing members arranged in an inclined slot in said table infront of the cutter-head, spring-actuated plungers arranged insaid'table in advance of said guideway, levers arranged on t-he underside of the table and operatively connected t-o said plungers, racks onthe ends of said levers, pinions coperating with said racks and providedwith arms, a link connecting each of said arms to the guard member WithIn testimony whereof I hereunto aiX my which it cooperates, a verticallydisposed signature in the presence of tWo Witnesses, guideWay on theunder side of the table this six day of July, 1912.

against Which said links bear, and a chip GEORGE W. SMITH. guard on theunder side of the table for Witnesses:

preventing chips from entering said guide- JOSEPH A. RIORDON,

Way. HENRY F. GILL.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

